shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-06-09 12:17:12 +09:00
Code Issues Packages Projects Releases Wiki Activity

mm: optimize thread stack usage on ARMv7 [1/1]

Browse Source 
PD#SWPL-2681

Problem:
Kernel stack usage is large when running many tasks.

Solution:
Map kernel stack to module space and handle page-fault
for stack fault. This can save about 50% memory of stack
usage

Verify:
p212

Change-Id: Ie894bc8f00cb525ddf8ac63c6d99d9c6e937fdc0
Signed-off-by: tao zeng <tao.zeng@amlogic.com>
This commit is contained in:
tao zeng
2018-11-30 18:01:31 +08:00
committed by Luke Go
parent 4b9ca77d52
commit 003b4e1f9b
19 changed files with 656 additions and 48 deletions
Download Patch File Download Diff File Expand all files Collapse all files

30
include/linux/amlogic/vmap_stack.h
View File

@@ -20,7 +20,18 @@
#define STACK_SHRINK_THRESHOLD (PAGE_SIZE + 1024)
#define STACK_SHRINK_SLEEP (HZ)
#ifdef CONFIG_64BIT
#define VM_STACK_AREA_SIZE SZ_512M
#define VMAP_ADDR_START VMALLOC_START
#define VMAP_ADDR_END VMALLOC_END
#define VMAP_ALIGN VM_STACK_AREA_SIZE
#else
/* currently support max 6144 tasks on 32bit */
#define VM_STACK_AREA_SIZE (SZ_64M - SZ_16M)
#define VMAP_ADDR_START MODULES_VADDR
#define VMAP_ADDR_END MODULES_END
#define VMAP_ALIGN SZ_64M
#endif
#define STACK_TOP_PAGE_OFF (THREAD_SIZE - PAGE_SIZE)
@@ -34,33 +45,28 @@
#define CACHE_MAINTAIN_DELAY (HZ)
struct aml_vmap {
spinlock_t vmap_lock;
unsigned int start_bit;
int cached_pages;
struct vm_struct *root_vm;
unsigned long *bitmap;
struct list_head list;
spinlock_t vmap_lock;
spinlock_t page_lock;
struct delayed_work mwork;
spinlock_t page_lock;
};
extern int handle_vmap_fault(unsigned long addr,
unsigned int esr, struct pt_regs *regs);
extern DEFINE_PER_CPU(unsigned long [THREAD_SIZE/sizeof(long)], vmap_stack);
static inline bool on_vmap_stack(unsigned long sp, int cpu)
{
/* variable names the same as kernel/stacktrace.c */
unsigned long low = (unsigned long)per_cpu(vmap_stack, cpu);
unsigned long high = low + THREAD_START_SP;
return (low <= sp && sp <= high);
}
extern bool on_vmap_stack(unsigned long sp, int cpu);
extern void __setup_vmap_stack(unsigned long off);
extern void update_vmap_stack(int diff);
extern int get_vmap_stack_size(void);
extern int is_vmap_addr(unsigned long addr);
extern void aml_stack_free(struct task_struct *tsk);
extern void *aml_stack_alloc(int node, struct task_struct *tsk);
extern void aml_account_task_stack(struct task_struct *tsk, int account);
#ifdef CONFIG_ARM
extern int on_irq_stack(unsigned long sp, int cpu);
#endif
#endif /* __VMAP_STACK_H__ */

10
include/linux/sched.h
View File

@@ -3331,7 +3331,13 @@ static inline unsigned long *end_of_stack(const struct task_struct *task)
#elif !defined(__HAVE_THREAD_FUNCTIONS)
#ifdef CONFIG_AMLOGIC_VMAP
#define task_thread_info(task) \
((struct thread_info *)(((unsigned long)(task)->stack) + \
THREAD_INFO_OFFSET))
#else
#define task_thread_info(task) ((struct thread_info *)(task)->stack)
#endif
#define task_stack_page(task) ((void *)(task)->stack)
static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
@@ -3351,11 +3357,15 @@ static inline void setup_thread_stack(struct task_struct *p, struct task_struct
*/
static inline unsigned long *end_of_stack(struct task_struct *p)
{
#ifdef CONFIG_AMLOGIC_VMAP
return p->stack;
#else /* CONFIG_AMLOGIC_VMAP */
#ifdef CONFIG_STACK_GROWSUP
return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1;
#else
return (unsigned long *)(task_thread_info(p) + 1);
#endif
#endif /* CONFIG_AMLOGIC_VMAP */
}
#endif